Dispensing head for lever-operated hand grease gun

ABSTRACT

A built-up, fused head assembly for a lever-operated hand grease gun and adapted for use with a thin walled grease container provides a high-pressure cylinder, formed from at least two parts, one of which is preferably made from round metal stock and the other from rectilinear metal stock. The cap is formed from relatively thin sheet metal stock and includes a channel-shaped wall area for receiving and supporting the high-pressure cylinder part formed from the round metal stock. The cap sidewalls have corrugated, roll-type threads for mating corresponding threads on the grease container. The head part, which is preferably formed of the rectilinear metal stock, can also provide the housing for the outlet check valve, and an extension of the cylinder bore can pass through the sidewall of the part, the extension being closed by a press-fitted plug, locked in place by metal deformation. Alternatively, the head part may comprise an integral part formed of rectilinear bar stock and providing an oversize extension of the cylinder bore. An enlarged depression is formed about the mouth of the oversize bore extension to provide a seating surface for receiving the round metal stock and being welded to it.

States Patent m1 3,627,178

[72] inventor E win E Sundholm Primary ExaminerRob en B. Reeves R.R. 1, Albert City, Iowa 50010 Assistant Examiner- Larry Martin [211 App]. No. 854,581 A!l0rneyDawson, Tilton, Fallon & Lungmus [22] Filed Sept. 2, 1969 [45] Patented Dec. 14, 1971 ABSTRACT: A built-up, fused head assembly for a leveroperated hand grease gun and adapted for use with a thin walled grease container provides a high-pressure cylinder, formed from at least two parts, one of which is preferably [54] DISPENSNG HEAD FOR LEVER OPERATED made from round metal stock and the other from rectilinear HAND GREASE GUN metal stock The cap lS formed from relatively thin sheet metal 14 Claims, 7 Drawing Figs stock and includes a channel-shapedwall area for receiving and supporting the high-pressure cylinder part formed from [52] U.S.Cl. 222/383, the round metal Stock. The cap Sidewalk have corrugated 105 A roll-type threads for mating corresponding threads on the [5 l Int. Cl B67d 3/00 grease comaineh The head part, which is f bl f d f [50] Field of Search '222/256, the rectilinear meta] Stock, can also provide the housing f 324; the outlet check valve, and an extension of the cylinder'bore 184/105 105 C can pass through the sidewall of the part, the extension being closed by a ress-fitted plug, locked in place by metal defor- [56] References Cited mation. Alteinatively, the head part may comprise an integral UNlTED STATES PATENTS part formed of rectilinear bar stock and providing an oversize 2.21 .3 WI 1940 Sundh lm 222/383 extension of the cylinder bore. An enlarged depression is 2,436,701 2/l948 Sundholm 222/383 formed about the mouth of the oversize bore extension to pro- 2,886,2l5 5/l959 Klein et al... 222/326 X vide a seating surface for receiving the round metal stock and 2,923.443 2/l960 Sundholm 222/256 being welded to it.

PATENTEU DEC 1 4 I97! sum 1 or 2 INVENTOR: EDWIN P. SUNDHOLM DISPENSING HEAD FOR LEVER-OPERATED HAND GREASE GUN BACKGROUND Lever-operated hand grease guns have been known and used for many years. The heads of such grease guns include a cylinder and piston arrangement for dispensing the grease at high pressure, the cylinder being arranged to extend transversely across the head, and the piston reciprocating therein being operated by a lever pivoted to the outer end of the piston and extending along the side of the grease barrel or container, thereby permitting the operator to hold the barrel ofthe gun with one hand and the other end or handle portion of the lever with the other for applying the pumping action to the cylinder. Such high-pressure cylinders operate at pressures of 8,000 to 12,000 p.s.i., and commonly utilize pressures of 10,000 p.s.i. or greater. Consequently, it is essential to provide a mechanically strong and completely sealed head construction which is sufficiently rugged to stand up under rough handling and sufiiciently durable to last for many years. At one time, it was common practice to form the cap and head as an integral casting. One of the first built-up head constructions is disclosed in my US. Pat. No. 2,218,363, which issued in 1940. An improvement in this construction, where the cap and cylinder part are connected by fusion, is disclosed in my U.S. Pat. No. 2,436,701, which issued in 1948. A still further improvement is shown in my U.S. Pat. No. 2,923,443 of 1960.

Heretofore, built-up head constructions, as shown in my above-cited patents, utilized square or rectilinear metal bar stock for fonning the high pressure cylinder, and the entire cylinder was formed from one integral piece of metal. Further, a separate metal part was used to provide the housing for the outlet check valve. In practice, the cap members of the builtup heads were formed of relatively heavy metal, such as 0.065 inch or thicker sheet metal stock, and threads were cut into the inner wall surface of the cap for engagement with cut threads on the barrel.

in prior practice, the grease gun barrels have been formed of relatively heavy tube stock, such as 0.065 inch or thicker stock, and the external threads for engagement with the cap have been formed by a thread cutting operation, in which metal is removed by the thread cutting tool. In my prior US. Pat. No. 3,089,161, a method is described for forming an internally threaded gasket-retaining cap for use in a grease gun dispensing head. According to this patent, the internal threads of the cap are formed by a thread rolling procedure, the metal on the inner wall of the cap being displaced, but the die members pressing the outer surface of the sidewall to a smooth noncorrugated surface. Where the cap has a thickness of 0.065 inch or greater, this type of thread rolling is necessary, since it is not feasible to form the threads by corrugating the relatively thick sidewall of the cap, as may be done with metal in thin gauges, such as 0.050 inch or thinner.

SUMMARY In accordance with the present invention, a lever-operated grease gun employs a fused, built-up dispensing head construction which is much less expensive to manufacture than previously known built-up heads, while at the same time providing a mechanically sound construction which is as reliable and durable as prior head constructions. More specifically, the novel dispensing head of this invention permits the use of relatively thin walled sheet metal stock for forming the cap around bar stock for forming the major portion of the cylinder bore, thereby greatly reducing the amount of metal required to form these portions of the head and resulting in considerable cost saving without sacrifice of mechanical performance.

The head construction may be completed by utilizing two inexpensive and easily manufactured screw machine parts one of the parts may be machined from bar stock to provide a continuation of the high-pressure cylinder bore as well as a housing for the outlet check valve, and the other part is a simple press plug for closing the outlet end of the high-pressure cylinder bore. This construction has the advantage of considerably reduced fabrication and material cost while permitting positive displacement of the grease throughout the entire cylinder stroke.

Alternatively, the head construction may be completed with a single integral part machined from bar stock to provide an oversize continuation of the high pressure cylinder bore as well as a housing for the outlet check valve. A recess is formed about the periphery of the mouth of the oversize continuation of the high pressure cylinder bore to provide a seating surface for receiving the round bar stock member and being welded to it. In this embodiment, the end of the round bar stock which fits into the peripheral recess also contains a short oversize bore portion. Although full positive displacement of the grease in this embodiment is not achieved in the oversize portion of the cylinder bore, it is more than offset by the lower cost and facility of fabrication and manufacture.

Another important advantage of the inventive construction is that the thin sidewalls of the cap permit the threads which receive the grease barrel to be formed by a corrugating, thread rolling procedure. The weight of metal in the barrel can thereby be greatly reduced; and the mating threads at its forward end may be formed by the same type of corrugating,

thread rolling procedure. For example, with the new construction, the barrel will have adequate strength and durability when formed from metal tube stock of 0.035 inch thickness. The head construction can be used on grease guns adapted for all types of filling, including cartridge, pressure, and suction filling.

THE DRAWING This invention is shown in illustrative embodiments in the accompanying drawing, in which:

FIG. 1 is a side elevational view of a first embodiment of a grease gun having a dispensing head and grease container constructed in accordance with the present invention, a portion of the cap and front end of the grease container being broken away to show the roll-thread connection between the cap and container;

FIG. 2 is a front end elevational view, as indicated by the line 2-2 in FIG. 1,

FIG. 3 is an exploded sectional view of the parts of the dispensing head of the embodiment of FIG. 1 prior to assembly;

FIG. 4 is a side sectional view of the assembled dispensing head ofFlG. 1;

FIG. 5 is a sectional view of the assembled head, taken on line 5-5 of FIG. 4;

FIG. 6 is an exploded view, in side cross section, of the parts of the dispensing head of an alternative embodiment; and

FIG. 7 is a side sectional view of the head of FIG. 6 with the parts assembled.

DETAILED DESCRIPTION Looking first at FIG. 1, there is shown a levenoperated hand grease gun having an elongated cylindrical grease container or barrel 10 which has an open forward end 11 and a closed rear end 12. Within the grease container 10 is a plunger 13 for urging the grease toward the forward end of the container. In FIG. 1, the plunger 13 is shown diagrammatically, since the construction of the plunger is not part of the invention, and plungers well known in the art can be employed. As indicated, the plunger 13 slides on and can be actuated by a plunger rod 14 which extends through the rear end 12 and terminates in a handle loop 15. Conventionally, a compression spring is provided behind the plunger 13, extending to a seating surface in the rear of the gun, thereby urging plunger 13 toward the forward end of the gun by spring pressure. This type of construction is also well known in the hand grease gun art, and does not form a part of the present invention. As will subsequently be described, however, the dispensing head construction of this invention, indicated generally by the letter B,

I ends 23 and 25 ofthe bore.

the art. v I I The dispensing head H includes a cap means designated 7 generally by the number 16 for attachment to the forward end I of the cylindrical grease container 10. The cap 16 provides a isadapted for use with grease containers or barrels formed I I from thinner metal than has heretofore been the'practice in rearwardly extending cylindrical sidewall portion l7 provided 1 Y with threads 18 for engaging the threads 19 at the forward end I of the grease container. The cap 16 also provides a transverse- I ly extending closure wall portion'20. A high-pressure cylinders providing means, designated generally by the number 21, is I mounted on the forward side of closure wall portion 20. The cylinder-providing means 21 has a transversely extending bore 22 open at its upper end 23 for receiving a piston 24, which reciprocates therein and bottoms at 25 adjacent the other end I of the bore 22. Inlet port means, which will subsequently be described in detail, extends through the cap wall 24) and through the cylinder-providing'means 21 intermediate the The assembly l-l also includes. a

valve connected to the adjacent discharge end of bore 22. Ex-

tending outwardly from housing 26 is an outlet pipe 27 (shown I I only in part). lt will be understood that pipe 27 will terminate in an adapter for connection to grease fittings'into, which the grease is to be pumped. The pump action is achieved'by means of a lever 28, which is pivoted at 29 to the projecting end of dle 29 with the. other, andlmoving the lever28 toward and the bore 22', and pump out the grease through pipe 27. Since this general method of operation is also well known in them, it is not believed that it will need to be furtherdescribed herein. I Y The dispensing head .Hof this invention constitutes an im- 7 housing designated I generally, by the. number 26 for containing an outlet check means than welding, such as brazing or soldering. However, a weld connection of thebutt or projection type ispreferred.

After the connection of the parts 21 and'26, the bore 22 can be reamed'to assure that the bore has a uniform diameter throughout its length, and thereafter broached to provide the final bore size and burnished to provide a mirror finish.

The foregoing assemblyand finishing operations for the bore 22 can all be performedbefore the insertion of the plug 34, and the reaming, breaching, and bumishing'operations are thereby greatly facilitated: Also, the assembled parts 21 and 2e are preferably attached to the cap. l6prior to the finishing operations and the insertion of the'plug' 34. With'the construc- I tion shown, this can be readily accomplished. I

The assembled bore-providing parts 21 and 26 are positioned on the front of cap wall 20, the weld'projection 39 being in contact with the adjacent wall of the part 26 and the projection 46D 'in'contact with the adjacent wall of the par't 21, as indicated by the dotted lines l and 11 in FIG. 3. The weld I 1 projections are fused to their wall, resulting in the weld area Bill: and the weld ring 4%, as'shown in FIG. 4.'A' s previously explained, the channel-shaped wall 41' receives and supports I the exteriorwall of part 21, which has a corresponding cylindrical shape. This is shown more clearly in FIG. 5.. It will be understood than the cap 16 may be connected to the assern- I i bledparts 2i and .26 by other suitable fusion means, such as bracing or'soldering. However, a projection weld-type connection is preferred. After-the connection of the parts 2lland 26 to the cap 16, a

port42 isformed, such as by drilling, the port extending through the wall 20 and the adjacent portion of the wall of part 21 to provide communication between the interior of the grease cylinder l0 and the bore '22 of the high-pressure cylinder when the cap is'mounte'd on the forward end of the I away from the grease container to reciprocate the piston 24 in cylinder, as shown in FIG. ii The drilling to form the port 42 can bealong the lines 11, as indicated in FIG. 3, the juncture I between the wall 20 and the adjacent portion 'of' the wall of part 21' being entirely surrounded and sealedby the weld 40a.

provement in the, design and manufacturing of built-up, fused dispensing heads Essentially, as shown in FIG. 3, the head H is I I formed from four parts; namely, the cap 16, the cylinderproviding part 21, the cylinder-providing part 26 (which also provides the housing for the outlet check valve), and a plug part 34. As indicated, the bore 22a of part 21 together with the bore 22b of the part 26 provide the bore 22. Part 26 also provides an extension of the bore designated as 220, which extends through the sidewall of the part 26.

To facilitate the assembly, the end of bore 22b which connects with the bore portion 22a is enlarged to provide a recess with an annular seating surface 36 at the bottom thereof. The lower end of part 21 is provided with an extension 37 dimensioned to be received within recess 35, and terminating in a tapered weld ring 38. The cylinder sidewall 3dr: of the plug 34 is slightly tapered, decreasing in diameter by a few thousandths of an inch from the point Y to the point x. The outer comer of the part is preferably beveled at 34b.

The wall 20 of cap 16 provides a weld projection 39 in the form of a small protuberance, and a weld projection All] in the form of a ring. The projection 40 is preferably formed within the recess provided by the forwardly facing channel-shaped wall 41, which has a cylindrical curvature for receiving and supporting the outside of part 211, as shown more clearly in FIG. 5.

The appearance of the assembled head can be seen more clearly in FIGS. 4 and 5. The parts 21 and 26 have been connected by the insertion of reduced end 37 into recess 36, a butt weld 380 being formed entirely around the bore 22 at the connection of the bore portions 22a and 2211. it will be understood that the bore-providing parts 21 and 26 can be butted together and connected by fusion to provide a pressure-type seal extending around the bore 22 by other fusion Preferably, the port 42 isformed prior to the final finishing operations for the bore 22.

- After the assembly of the parts 21 and 26 to the cap 16, as described,,and.the finishing'of the bore 22, the plug 34 can be I inserted. The diameter at the point x of the plug will be substantially the same or slightly less than that of the bore extension 22c, while the diameter at the point y will be slightly greater than that of the bore extension. When the plug 34 is driven into the bore extension 220, there will result a tight press-fit which will provide a seal for the outlet end of the bore 22. To assure that the plug 34 is retained and hermetically sealed, metal at the outer end of the bore extension 22c can be deformed, such as being formed inwardly over the outer end of the plug 34,. This staking" of the plug 34 in place can advantageously take the form of a spun-over shoulder 43 which overlies and engages the beveled shoulder 34a of the plug, as shown more clearly in FIG. 4.

The wall 20 may be provided with a port for receiving a removable threaded plug 46, as shown in H68. 1 and 2. As is well known in the art, the plug 46 can be removed for attachment of a grease supply pipe in the pressure filling of the grease gun. The forwardly extending portion 47 of the part 26 can provide the housing for the outlet check valve. As shown more clearly in FlG. i, a port 48 communicates with the closed end of bore 22, and on its outer side provides a seat for ball valve 419, which is spring biased towards the seat by compression spring 50. The spring 50 is held in place by the inner end of the outlet pipe 27.

Turning now to the embodiment of FIGS. 6 and 7, for convenience in relating elements shown therein to those already described, similar elements or components will be identified by like reference numerals preceded by a 1." The dispensing head of this embodiment comprises three separate parts, a cap generally designated 116, a cylindrical part which defines a major portion of the high-pressure cylinder bore and generally designated 112i, and a housing member 1126 for providing a continuation of the high-pressure cylinder bore as well as a housing for the outlet check valve (not shown). The cap 116 includes a rearwardly extending cylindrical sidewall portion 117 in which there are formed threads 118 for receiving corresponding mating threads at the forward end of the grease container or barrel, similar to the previously described container 10. The cap 116 also includes a transverse forward closure wall 120.

The cylinder member 121 defines a transverse bore 122 which receives a piston 124. A piston 124 reciprocates in the cylinder bore and bottoms at 125 adjacent the lower end of the bore 122 as viewed in the drawing.

The bore 122 includes an upper segment 122a formed longitudinally of and coaxial with the member 121, and a lower segment 122b formed in the bar stock member 126. The upper portion 122a of the bore 122 is expanded to a larger diameter at its lowermost opening adjacent the member 125, as at 1220; and the diameter of the expanded portion of the bore 1220 is the same as the diameter of the bore portion 122b in the lower member 126. About the mouth of the bore portion 122b there is formed a recess or groove 135, the lower surface of which 136 provides a seating surface for receiving the upper boredefining member 121 which is provided with a lower peripheral extension 137 dimensioned to be received in the groove 135. The extension 137 defines, at its lowermost edge, a tapered weld ring 138 for engaging the seating surface 136 of the groove 135 and being welded thereto.

As with the previous embodiment, the part 125 is provided with a three-stage bore 147 including an internally threaded portion 148 for receiving an outlet pipe, an intermediate chamber 149 for housing a spring in compression, and an end chamber 150 for receiving a ball valve. The far end of the chamber 150 is provided with a seating surface 151 for sealingly engaging a ball; and the chamber 150 communicates with the lower portion 122b of the bore 122 via a conduit 152.

Turning now to the forward wall 120 of the cap 116 as seen in FIG. 6, a small protuberance 139 is located along the vertical center line of the wall 120 and toward its lower end for forming a weld projection for welding to the member 125. A similar upper weld projection is designated 139a for engaging and being welded to the member 121 after it is assembled to the housing member 125, as will presently be described.

As with the previous embodiment, the front wall 120 of the cap 116 is formed into a forwardly facing channel-shaped structure generally designated 141 including first and second vertical (as viewed in the drawing) ridges, the far one of these ridges being shown in FIG. 7 and designated 141a. The two ridges are joined by a curved, integral support wall which defines a recess for receiving and supporting the part 121 similar to the manner in which the part 21 is received in the channel 41 of the previous embodiment as illustrated in FIG. 5. A weld projection 140 in the form of a ring is formed within the recess provided by the channel-shaped wall 141.

The fabricated dispensing head is illustrated in FIG. 7. The parts 121 and 126 have been secured together by the insertion of the extension 138 of the part 121 into the peripheral recess 136 of the part 126. A butt weld is formed entirely about the mouth of the lower channel portion 122b by means of the weld ring 133 being welded to the seating surface 136 of the recess 135. It will be observed that when the two parts are thus assembled, the bore portion 1220 of the member 121 forms a continuation of the cylindrical sidewall of the lower bore portion 122b formed in the part 126; and this combined portion of the bore 122 provides an annular clearance (or oversize segment) designated 155 which surrounds the lower portion of the cylinder 124 and extends from the bottom 125 upward past the welded pressure seal between the two parts 121 and 126. The oversize portion 155 of the bore 122 extends past this junction and into the lower portion of the bore 122a so as to avoid interference with the reciprocating piston after the weld is formed.

Above the oversize bore portion 155, the interior cylindrical surface of the bore 122 is a highly polished surface so as to form a seal with the cylinder member 124. The clearance of the oversize portion 155 need only be 5-10 mils greater in diameter than the portion 1220 of the bore; and this is preferably done by machining. Although the construction of FIGS. 6 and 7 does not provide full positive displacement of grease in the high-pressure pump mechanism, the additional volume of grease stored in the clearance 155 when the piston is fully inserted is negligible in comparison with the advantages afforded by this construction.

Prior to the welding (or similar pressure-type fusing) of the parts 121 and 126, the bore 122 may be reamed to assure that it has a uniform diameter throughout the portion extending above the clearance 155. The final bore size is provided by broaching; and the mirror finish is, again, provided by bumishing. The weldment may be fusion welded to the forward wall of the cap 16 by means of the weld projections 139, 139a and the projection ring 140 which extends entirely about the periphery of a port drilled through the forward wall and the side of the bore-defining member 121, as at 142, to communicate the interior container with the bore 122 when the cap is secured to the forward end of the cylinder (see FIG. 1).

Since one of the important advantages of the present invention is economy of materials, further details of preferred commercial embodiments will now be set forth. The grease container or barrel is preferably formed from a low carbon steel, which is purchased as tube stock in the desired gauge. Gauges or thicknesses of less than 60 mils are preferred, such as a thickness of 35 mils. Tube stock having wall thickness of less than 30 mils may not be sufficiently durable, but may be used for some purposes. The cap 16 can be formed from metal sheet stock, such as low carbon steel sheets of a thickness less than 60 mils, for example 50 mils. While sheet stock down to 30 mils thickness can be used, it will usually be preferable to use sheet stock of at least 40 mils thickness for forming the cap.

The parts 21 and 121 can be manufactured from low carbon steel rod stock of round cross section. The selected diameter will depend on the desired size of the bores 22 and 122, but the amount of metal required will be substantially less than if stock having a rectilinear cross section were used. The parts 26 and 126 are preferably formed of bar stock having a rectilinear cross section, but these parts provided only a small portion of the bores.

Having thus described in detail alternative embodiments of the present invention, persons skilled in the art will be able to modify portions of the structure shown and to substitute equivalent elements for those described without departing from the inventive principle; and it is, therefore, intended that all such modifications and substitutions be covered as they are embraced within the spirit and scope of the invention.

I claim:

1. In a lever-operated hand grease gun, including cap means providing a rearwardly extending cylindrical sidewall portion and a transversely extending closure wall portion, a cylindrical grease container having a forward end portion received within said cap sidewall portion, high-pressure cylinder-providing means mounted on the forward side of said closure wall portion, said cylinder-providing means having a transversely extending bore open at one end for receiving a piston and closed at the other end, inlet port means extending through said cap closure wall and through said cylinder-providing means intermediate the said ends of said bore, and housing means for containing an outlet check valve connected to the portion of said cylinder-providing means adjacent the closed end of said bore, wherein the improvement comprises: said cylinder-providing means being built up from at least two separate metal parts, one of said parts providing the portion of said bore extending from said open end toward said inlet port means, and another of said parts providing the portion of said bore extending from said closed end past said inlet port means, said bore-providing parts being butted together and connected by fusion, said one part having a cylindrical exterior concentric with the bore portion therein, said cap means being formed of metal sheet stock having a thickness of less than 60 mils and providing a forwardly facing channel-shaped wall area for receiving and supporting the portion of said one part surrounding said inlet port means, said wall area and said supported first part portion being united by fusion around said inlet port means, said grease container being formed of metal tube stock having a wall thickness of less than 50 mils, the said forward end portion of said grease container and said cap sidewall portion being provided with matching rolled thread corrugations.

2. The improvement of claim ll characterized by the further fact that said other part provides a forwardly extending portion comprising said outlet check valve housing means.

3. The improvement of claim 1 characterized by the further fact that said one part is formed from metal stock having a round cross section and said other part is formed from metal stock having a rectilinear cross section.

4. The improvement of claim 2, characterized by the further fact that said other part provides an extension of said bore through the sidewall thereof opposite said connection with said one part, and a third part is provided comprising a plug received in and sealing said bore extension, said plug part engaging the walls of said bore extension with a pressfit and being secured therein by metal deformation around the outer peripheral portion of said plug part.

5. A fabricated high-pressure dispensing head for a hand grease gun comprising three separate metal parts secured together into a unitary construction including a cap formed of sheet metal having a thickness of less than 60 mils and having a rearwardly extending cylindrical sidewall defining corrugated roll threads for receiving a cylindrical grease container and a forward closure wall for partially containing the grease, a first elongated part attached to said closure wall of said cap and defining a bore extending longitudinally therethrough for receiving a piston, and having a lower open end, said bore communicating with the interior of said container through said first part and said forward wall of said cap; and a second part fused to said first part about said lower open end and providing a continuation of said bore, said second part defining a bottoming surface for limiting the insertion of said piston and outlet means adjacent said bottoming surface for admitting passage of said grease.

6. The structure of claim 5, wherein said second part further defines a chamber for housing a check valve, said chamber communicating with said continuation of said bore in said second part through said outlet means adjacent said bottoming surface.

7. In combination with the structure of claim 5, a cylindrical grease container having a wall thickness of less than about 40 mils and is formed into corrugated roll threads at one end for mating the roll threads of said cap in sealing engagement.

8. The structure of claim 5, wherein said first part is formed from cylindrical bar stock having a wall thickness of less than 60 mills and wherein the outer surface of said closure wall of said cap form a transversely extending curved channel for receiving said first part and conforming to the exterior surface thereof.

9. A fabricated high-pressure dispensing head for a hand area, a second part having a cylindrical exterior and a longitudinally extending bore therein received in said channel-shaped wall area, said bore communicating with the other side of said cap through aligned openings in the wall of said second part and the wall of said first part, and a third part providing an extension of the bore of said first part and a passage extending forwardly from the end of said extension to provide an outlet check valve housing.

10. The structure of claim 9, in which the bore in the second part is radially enlarged adjacent the third part, the third part being provided with a bore having a diameter substantially the same as the diameter of the radially enlarged portion of the bore of the first part and providing said bore extension, the third part also being provided with a radially enlarged recess about the bore therein having a seating surface extending generally transversely from the bore, the second part being received in the recess in the third part and abutting the seating surface, the second and third part being connected by fusion.

11. in a lever-operated hand grease gun, including cap means providing a rearwardly extending cylindrical sidewall portion and a transversely extending closure wall portion, a cylindrical grease container having a forward end portion received within said cap sidewall portion, high-pressure cylinder-providing means mounted on the forward side of said closure wall portion, said cylinder-providing means having a transversely extending bore open at one end for receiving a piston and closed at the other end, inlet port means extending through said cap closure wall and through said cylinderproviding means intermediate the said ends of said bore, and housing means for containing an outlet check valve connected to the portion of said cylinder-providing means adjacent the closed end of said bore, wherein the improvement comprises: said cylinder-providing means being built up from at least two separate metal parts, one of said parts providing the portion of the bore extending from said open end past the inlet port means, and another of said parts providing the portion of the bore extending from said closed end toward the inlet port means, the portion of the bore in said other part having a diameter greater than the diameter of the bore through said one part from the open end past the inlet port means, the bore through said one part terminating past the inlet port means in a radially enlarged portion having a diameter substantially the same as the diameter of the bore in the other part, the other part being provided with a radially enlarged recess about the mouth of the bore therein, said one part being received by the recess in said other part and being connected to said other part by fusion.

12. The improvement of claim 11, characterized by the further fact that said other part is integrally formed and provides a forwardly extending portion comprising said outlet check valve housing means.

13. The improvement of claim 11, characterized by the further fact that one part is formed from metal stock having a round outer surface and terminating in an end portion having a diameter less than the diameter of the outer surface, the end portion of said one part being received in the recess of the other part.

24. The improvement of claim 11, characterized by the further fact that said cap means is formed of metal sheet stock having a thickness of less than 60 mils and provides a forwardly facing channel-shaped wall area for receiving and supporting the portion of said one part surrounding said inlet port means, the cap sidewall portion being provided with rolled thread corrugation. 

1. In a lever-operated hand grease gun, including cap means providing a rearwardly extending cylindrical sidewall portion and a transversely extending closure wall portion, a cylindrical grease container having a forward end portion received within said cap sidewall portion, high-pressure cylinder-providing means mounted on the forward side of said closure wall portion, said cylinder-providing means having a transversely extending bore open at one end for receiving a piston and closed at the other end, inlet port means extending through said cap closure wall and through said cylinder-providing means intermediate the said ends of said bore, and housing means for containing an outlet check valve connected to the portion of said cylinder-providing means adjacent the closed end of said bore, wherein the improvement comprises: said cylinder-providing means being built up from at least two separate metal parts, one of said parts providing the portion of said bore extending from said open end toward said inlet port means, and another of said parts providing the portion of said bore extending from said closed end past said inlet port means, said bore-providing parts being butted together and connected by fusion, said one part having a cylindrical exterior concentric with the bore portion therein, said cap means being formed of metal sheet stock having a thickness of less than 60 mils and providing a forwardly facing channel-shaped wall area for receiving and supporting the portion of said one part surrounding said inlet port means, said wall area and said supported first part portion being united by fusion around said inlet port means, said grease container being formed of metal tube stock having a wall thickness of less than 50 mils, the said forward end portion of said grease container and said cap sidewall portion being provided with matching rolled thread corrugations.
 2. The improvement of claim 1 characterized by the further fact that said other part provides a forwardly extending portion comprising said outlet check valve housing means.
 3. The improvement of claim 1, characterized by the further fact that said one part is formed from metal stock having a round cross sEction and said other part is formed from metal stock having a rectilinear cross section.
 4. The improvement of claim 2, characterized by the further fact that said other part provides an extension of said bore through the sidewall thereof opposite said connection with said one part, and a third part is provided comprising a plug received in and sealing said bore extension, said plug part engaging the walls of said bore extension with a press-fit and being secured therein by metal deformation around the outer peripheral portion of said plug part.
 5. A fabricated high-pressure dispensing head for a hand grease gun comprising three separate metal parts secured together into a unitary construction including a cap formed of sheet metal having a thickness of less than 60 mils and having a rearwardly extending cylindrical sidewall defining corrugated roll threads for receiving a cylindrical grease container and a forward closure wall for partially containing the grease, a first elongated part attached to said closure wall of said cap and defining a bore extending longitudinally therethrough for receiving a piston, and having a lower open end, said bore communicating with the interior of said container through said first part and said forward wall of said cap; and a second part fused to said first part about said lower open end and providing a continuation of said bore, said second part defining a bottoming surface for limiting the insertion of said piston and outlet means adjacent said bottoming surface for admitting passage of said grease.
 6. The structure of claim 5, wherein said second part further defines a chamber for housing a check valve, said chamber communicating with said continuation of said bore in said second part through said outlet means adjacent said bottoming surface.
 7. In combination with the structure of claim 5, a cylindrical grease container having a wall thickness of less than about 40 mils and is formed into corrugated roll threads at one end for mating the roll threads of said cap in sealing engagement.
 8. The structure of claim 5, wherein said first part is formed from cylindrical bar stock having a wall thickness of less than 60 mils and wherein the outer surface of said closure wall of said cap form a transversely extending curved channel for receiving said first part and conforming to the exterior surface thereof.
 9. A fabricated high-pressure dispensing head for a hand grease gun, comprising at least three separate metal parts secured together in a unitary construction, said construction including as one of said parts a cap formed of sheet metal having a thickness of less than 60 mils and having a rearwardly extending cylindrical sidewall defining threads for receiving a cylindrical grease container, said cap also providing a forward closure wall providing a forwardly facing channel-shaped wall area, a second part having a cylindrical exterior and a longitudinally extending bore therein received in said channel-shaped wall area, said bore communicating with the other side of said cap through aligned openings in the wall of said second part and the wall of said first part, and a third part providing an extension of the bore of said first part and a passage extending forwardly from the end of said extension to provide an outlet check valve housing.
 10. The structure of claim 9, in which the bore in the second part is radially enlarged adjacent the third part, the third part being provided with a bore having a diameter substantially the same as the diameter of the radially enlarged portion of the bore of the first part and providing said bore extension, the third part also being provided with a radially enlarged recess about the bore therein having a seating surface extending generally transversely from the bore, the second part being received in the recess in the third part and abutting the seating surface, the second and third part being connected by fusion.
 11. In a lever-operated hand greaSe gun, including cap means providing a rearwardly extending cylindrical sidewall portion and a transversely extending closure wall portion, a cylindrical grease container having a forward end portion received within said cap sidewall portion, high-pressure cylinder-providing means mounted on the forward side of said closure wall portion, said cylinder-providing means having a transversely extending bore open at one end for receiving a piston and closed at the other end, inlet port means extending through said cap closure wall and through said cylinder-providing means intermediate the said ends of said bore, and housing means for containing an outlet check valve connected to the portion of said cylinder-providing means adjacent the closed end of said bore, wherein the improvement comprises: said cylinder-providing means being built up from at least two separate metal parts, one of said parts providing the portion of the bore extending from said open end past the inlet port means, and another of said parts providing the portion of the bore extending from said closed end toward the inlet port means, the portion of the bore in said other part having a diameter greater than the diameter of the bore through said one part from the open end past the inlet port means, the bore through said one part terminating past the inlet port means in a radially enlarged portion having a diameter substantially the same as the diameter of the bore in the other part, the other part being provided with a radially enlarged recess about the mouth of the bore therein, said one part being received by the recess in said other part and being connected to said other part by fusion.
 12. The improvement of claim 11, characterized by the further fact that said other part is integrally formed and provides a forwardly extending portion comprising said outlet check valve housing means.
 13. The improvement of claim 11, characterized by the further fact that one part is formed from metal stock having a round outer surface and terminating in an end portion having a diameter less than the diameter of the outer surface, the end portion of said one part being received in the recess of the other part.
 14. The improvement of claim 11, characterized by the further fact that said cap means is formed of metal sheet stock having a thickness of less than 60 mils and provides a forwardly facing channel-shaped wall area for receiving and supporting the portion of said one part surrounding said inlet port means, the cap sidewall portion being provided with rolled thread corrugation. 